Moiré pattern

Interference pattern

In mathematics, physics, and art, a moiré pattern (UK: MWAH-ray, US: mwah-RAY, French: [mwaʁe]) or moiré fringe is a large-scale wave interference pattern that can be produced when a partially opaque ruled pattern with transparent gaps is overlaid on another similar pattern. For the moiré interference pattern to appear, the two patterns must not be completely identical, but rather displaced, rotated, or have slightly different pitch. Moiré patterns appear in many situations.

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